Measured service telephone system



April 5, 1938.

T. F. CROCKER ET AL 13,080

MEASURED SERVICE TELEPHONE SYSTEM I Filed March '7, 1936 17 Sheets-Sheet 1 LINE SWITCH FIG.

AUTOMATIC PAYS TAT! ON INVENTORS NORMAN H. SAUNDERS THOMAS F. CEOCKER BY Z cLpslvcs E. LOMZ ATTORNEY.

April 5, 1938.

T. F. CROCKER ET AL MEASURED SERVICE TELEPHONE SYSTEM Filed March 7, 1936 1' 7 Sheets-Sheet 3 April 5, 1938. T. F. CROCKER ET AL MEASURED SERVICE TELEPHONE SYSTEM Filed March- 7, 1936 17 Sheets-Sheet 4 Ian 7 I 3m E Q\ Qua , mm u Q r Q, a

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17 I an m2:

wwm 8 Rm w E I 56 Es m5 EN N 953i $3.950 323mb wmm INVENTORS ,NORMAN H. SAUNDERS THOMAS F. CQOCKEI? CLARENCE E. LOMA A TTORNEY.

April 5, 1938. T. F. CROCKER ET AL MEASURED SERVICE TELEPHONE SYSTEM 17 Sheets-Sheet 5 Filed March '7, 1936 NOJPMAN H. SAUNDERS THOMAS F. CROCKED age/v05 E. LOM

1N VENTORS ATTORNEY.

A ril 5, 1938. 1'. F. CROCKER ET AL MEASURED SERVICE TELEPHONE SYSTEM 17 Sheets-Sheet 6 Filed March 7, 1936 INVENTORS NORMAN H. SAUNDERS THOMAS F. cRoc/(ER CLAfQENCE E. LOMA%:

ATTORNEY.

April 5, 1938.

T. F. CROCKER ET AL MEASURED SERVICE TELEPHONE SYSTEM 1L7 Sheets-Sheet 7 Filed March '7, 1936 FINDER LINK sa2 65/ 1 MON/TOR Wwa 4 KEY 68/ RING 644 I 75 602 SWITCH 645 K I 5/2 335 aflt. TIP HG-P 76 77; 7 677 582 V603 65a 4 636 6'55 684 60 656 685 as? i 605 as: CALL 606 1 624 I 635 6/5 CWNECT G88 L CAM 650 SWITCH g? 6/6" POLAR. 67/ 657 VERI BANK I START i 55 [3/61 6/0 Ewan/5, 6

ATTORN Y.

INVENTORS NORMAN H. SAUNDERS THOMAS F. CDOCKEP N CE E. LOMAZ April 5, 1938. 1i F. CROCKER ET AL 2,113,080

MEASURED SERVICE TELEPHONE SYSTEM Filed March 7, 1936 17 Sheets-Sheet 8 F/NDER- LINK 8 Y 7 PART-2 ANS. SUPY.

INVENTORS NORMAN H. SAUNDERS THOMAS F. CQOCKEQ BY I CLA'BENCE E. LOMA I ATTORNE T. F. CROCKER ET AL MEASURED SERVICE TELEPHONEESYSTEM April 5, 191 58.

17 Sheets-Sheet 10' Filed March 7, 1936 1N VENTORS NORMAN H. 5A UNDERS THOMAS F. CROCKER BY CLARE cs E. LOMAX ATToRNEY April 5, 1938. T. F. CROCKER ET AL MEASURED SERVICE TELEPHONE SYSTEM Filed March 7, 19256 1'7 Sheets-Sheet l1 NNQ wm 3 I mNQ INVENTORS NORMAN H. SAUNDERS THOMAS F. CROCKEQ CLARENCE E. LOMAX ATTORNEY? April 5, 1938. T. F. CROCKER ET AL MEASURED SERVICE TELEPHONE S YSTEM Filed March 7, 1936 17 Sheets-Sheet 12 am W2 l 4 3: Q T F 2 2R E w E Nmm 3% W NE NE JI'IIJ \vfi g a Eek-Um Hwm April 5, 1938. T. F. CROCKER ET AL MEASURED SERVICE TELEPHONE SYSTEM Filed March 7, 1956 17 Sheets-Sheet 13 S v S X m H NCM U00 W NAR SC O W E m C wkm mm my $7 m3 Y B April 5, 1938. T. F. CROCKER ET AL 2,113,080

MEASURED SERVICE TELEPHONE SYSTEM I 17 Sheets-Sheet 14' Filed March 7, 193a MQQ - INVENTORS NORMAN H. SAUNDERS THOMAS F. CROCKER BY CLARENCE E. LOMAX.

' ATTORNEY.

'r. F. CROCKER :1- AL 2,113,080

MEASURED SERVICE TELEPHONE SYSTEM April s, 1938.

Filed March 7, 1956 1'? Sheets-Sheet l6 T. F. cRoCKER El AL MEASURED SERVICE TELEPHONE SYSTEM April 5, 1938.

Filed March 7, 1936 1'7 Sheets-Sheet 17- 5:36 8358 gt EQE Patented Apr. 5, 1938 UNITED STATES PATENT OFFICE 2,113,080 MEASURED SERVICE TELEPHONE SYSTEM Application March 7,

25 Claims.

The present invention relates in general to measured telephone systems, and more particularly to means for controlling the collection and refunding of coins deposited in paystation apparatus.

The main object of the present invention is the provision of a new and novel circuit arrangement by means of which an operator can control the collection or refund of deposited coins in the healer distant exchanges.

Another object of the invention is the provision of a novel two-way trunk circuit connecting the local and distant exchanges which is controlled by the operator to collect or refund coins on both incoming and outgoing calls made over this trunk circuit.

A further object of the invention is the provision of an improved line circuit for a paystation line wherein if the operator fails to collect or refund the deposited coin the operator is automatically resignalled on the release of the connection.

A feature of the invention relates to a novel paystation repeater individual to certain con- I nector switches for use by the operator in completing calls to paystation lines.

Another feature of the invention relates to the means in the two-way trunk circuit whereby the operator may ring back over the trunk line to ring the calling paystation line.

A further feature relates to the operator-controlled means for completing delayed calls to paystation lines and in which a common sender is first used .to control automatic switches to set up the connection to. the original calling line and thereafter'used to control other switches to complete the connection to the desired called line.

A still further feature relates to the means in the two-way trunk circuit for enabling the operator at the distant exchange to momentarily reconnect paystation tone to the trunk line conductors to verify that a paystation line is calling.

An additional feature relates to the means controlled by the operator whereby only certain classes of calls, such as calls from paystation lines, may be answered 'from an operator's position.

Other features of the invention not specifically mentioned will be apparent-from the following description.

Referring now to the drawings comprising Figs. 1 to 19, inclusive, Fig. 1 shows an automatic paystation subscribers line and a rotary lineswitch.

Fig. 2 shows one of the paystation repeaters accessible to the rotary line switches.

1936, Serial No. 67,644

Fig. 3 diagrammatically illustrates the first selector individual to the paystation repeater in the upper left-hand portion, and in the remainder .of the figure shows a portion of the trunk circuit connected to the distant exchange.

Fig. 4 shows the remainder of the trunk circuit and the two conductors extending to the distance exchange. 1

Fig. 5 diagrammaticallyillustrates an incoming selector accessible from the trunk circuit shown in Figs. 3 and 4 and which selector has access to connectors one of which is shown in the remainder of Fig. 5. The connector in Fig. 5 has access to regular subscribers lines and also to paystation lines, one of which is shown in Fig. 1.

Fig. 6 in its upper portion shows the trunk circuit at the distant exchange which is accessible to the finder links, one of which is shown in Figs. '7 and 8, and to the selector switches, one of which is shown in Fig. 12. The lower portion of Fig. 6 shows a delayed call trunk circuit accessible from the first level of the finders and an associated selector switch which has access to the exchange trunk line and to paystation control circuits, one of which is shown in Fig. 13.

Figs. '7 and 8 show one of these finder link circuits. The finder links have access to the trunk circuits such as shown in Fig. 6, to the manual paystation line circuits and to other circuits not shown.

Fig. 9, in the left-hand portion, shows the manner in which the start leads of the various circuits are connected to the vertical banks of the finder links. In the lower left-hand portion is shown the distributor for allotting one of the operators position for use on a call. The remainder, of Fig. 9 discloses the operators headset and a portion of the relays for operator's position No. 1.

Fig. 10 discloses the connecting relays in this operators position for connecting with the finder links.

Fig. 11 shows the operators keyset associated with this position for controlling the desired functions.

Fig. 12 discloses the selector individually connected to the finder link in Figs. '7 and 8, and this selector has access to paystation control circuits, one of which is shown in Fig. 13, and to trunk circuits, one of which is shown in Fig. 6.

Fig. 13 shows one of the paystation control circuits accessible to the selector. This paystation control circuit is individual to the connector diagrammatically shown in the right-hand portion of Fig. 13. This connector has access to the manual paystation lines, one 01' which is shown in Hg. 14.

Fig. 14 shows a manual paystation subscriber's line and the manual paystation line circuit which terminates in the bank of the finder links.

Fig. 15 diagrammatically illustrates the coin control circuits in schematic form for the automatic exchange, while Figs. 16 and 17 diagrammatically illustrate the coin .collect circuits in schematic form in the distant exchange.

Fig. 18 is a drawing layout showing the manner which the various figures are to be assembled. Fig. 19 is a drawing layout showing the manner in which the schematic coin collect layout figures are to be assembled.

The coin collector apparatus A shown in Fig. 1

may be oi the well known type of coin collecting Y mechanism such as shown and described in U. S. Patent to Forsberg No. 1,043,219, granted November 5, 1912. The lineswitch shown in Fig. 1 may be of the well known rotary type of lineswitch in which the wipers have no normal position, always remaining in engagement with the bank contacts associated with the trunk line last used. At T is shown a discriminating tone machine whose function is to give a discriminating tone to a recording operator should one be called by the subscriber, in order to inform her of his status,

that is whether he is entitled to certain connec-v tions or not. The paystation repeater circuit shown in Fig. 2 is somewhat similar to the paystation repeaters shown in Patent No. issued to John Wicks on October 11, 1927, and the Patent No. 1,909,025, issued to V. S. Tharp on May 16, 1933. The selector switches shown in Figs. 3, 5, 6, and 12 are known asbattery-searching selectors oi the well known Strowger vertical and rotary type, in which the test wiper of the selector hunts for battery potential'before switching through. These selectors are somewhat similar to the selector LS shown in Fig. 1 of Patent No. 1,971,505, issued to N. H. Saunders on August 28, 1934.

The connector switches shown in Figs. 6 and 13 are of the well known Strowger vertical and rotary type and are somewhat similar to the connectors shown in Fig. 3 of Patent No. 1,971,505. The finder link shown in Figs. 7 and 8 comprises the well-known Strowger vertical and rotary finder which is operated step by step in a vertical direction to the proper level under control of the vertical test wiper to find the proper group and is thereafter operated in a rotary step-by-step movement to find the calling line in the selected level. As is shown in the instant application, the finder is shown as having access to only the first, the eighth, and the ninth levels, it being understood that-the remaining levels of the finder are used for other classes of service not concerned with this invention. In the lower right-hand corner of Fig. 8 is diagrammatically shown a register sender link-and a register sender. This sender link and register sender is similar to the sender link and register sender shown in Figs. 22 and 23 of the Voss et 9.1. application, Ser. No. 40,686, filed September 16, 1935. Each operator's position is provided with a set of digit keys by means of which the operator may set up the called digits in the register sender. The sender links are used to connect the register sender to the finder link in use in this operators position. Figs. 9, 10, and 11 show one of the operators positions in a system commonly referred to as the Strowger dial toll board. Each operator's position has a number or finder links associated therewith by means 01' which the operator may extend the desired connection. Figs. 7 and 8 show only one of the finder links individual to the operator's position shown in Figs. 9, 10, and 11. The distributor shown in Fig, 9 is used to select one o! the tour operator's positions. In the upper lefthand corner 0! Fig. 9 is shown the start leads which extend from the-manual paystation line circuit of Fig. 14 and the trunk circuit of Fig. 16 and the other start circuits for the other classes of lines terminating in the banks or the finder. The operator is provided with a toll switching key for controlling the circuit of relay IIII so that if desired the finder shown in Figs. 7 and 8 may be used for only certain classes of calls In order to explain the operation of the circuits it will first be assumed that a party wishes to extend a call from the automatic paystation A to a subscriber in the distant manual exchange, ind that the party attempts to do so without first depositing a coin in the coin collecting mechanism at the paystation.

when the receiver is removed at substationA, line relay 26 01' the individual lineswitch C is energized over the two sides of the calling line in series. Relay 26, upon operating, at its armature 40 completes a circuit which includes the switching relay 25 and the motor magnet 21 in series, and at its armature 39 connects the test wiper 46 to the above circuit at a point midway between the switching or cut-ofl relay 25 and said motor magnet. The operation of the lineswitch 0 depends upon whether the trunk line with which its wipers 44 to 41, inclusive, are in engagement is busy or not. Assuming this line to be busy, there will be ground potential present upon the test contacts engaged by the test wiper 46, the switching relay 25 will be short circuited, and the motor magnet 21 will be supplied with direct ground by the test wiper to operate as a buzzer to advance the switch wipers step by step in search of an idle trunk line. However, it will be assumed in the present case that when the receiver is removed at substation A, the switch wipers 44 to 41, inclusive, are in engagement with the bank contacts associated with an idle trunk line. Under these conditions, immediately following the energization of line relay 26 switching relay 25, not being short circuited, will energize. Upon energizing, relay 25 disconnects the line conductors II and i2 of the calling substation from the winding of the line relay 26 and from ground respectively, and extends them by way of armatures 33 and 36, wipers 44 and 41, bank contacts 52 and 55, conductors 48 and 5|, armatures I45 and I44 and their back contacts, armatures I60 and I64 and their back contacts, upper and lower windings of the differential relay I30, and thence through the windings of line relay I35 and the windings of the impedance coil I39, to battery and ground, respectively. The line relay I35 of the repeater shown in Fig. 2 is energized over the two sides of the calling line in series and at its armature I83 completes the circuit for slowto-release relay I36 from ground by way of armature I62 and back contacts of relay I28. Relay I36 therefore energizes and at its armature I86 places ground on release trunk conductor 50 by way of the retardation coil I38, thereby establishing a holding circuit for lineswitch'C which extends by way of bank contacts 54, wiper 46, armature 35 and front contact, winding of relay 25, and thence through the winding of motor magnet 21 to battery. It will be understood that this holding circuit is completed before the slow-torelease relay 26 has had time to deenergize after its circuit was opened by relay 25. A branch of the holding circuit also extends by way of private normal conductor 498 to the multipled test contacts in the banks of the connector switches which have access to the line of substation A, whereby that line is protected from intrusion in the well known manner. It will be remembered that ground is supplied to the release trunk conductor 50 through the retardation coil I38. This coil is .01 a very low resistance, of about two-and-onehalf ohms, so that the multiples of the test contacts accessible to other line switches are made b l t elay I36, upon energizing, also completes at its armature I88 a circuit for the polarizing winding of the electro-polarized relay I32 in series with the winding of relay I H. The electropolarized relay I32 is so adjusted that current flowing in its polarizing winding does not cause this relay to operate its armature, but after once operating, the current fiow in the polarizing winding is --suflicient to maintain the armature attracted. Relay MI is, therefore, the only relay operated in this circuit. Relay l4l, upon energizing, opens a point in a certain shunt circuit which will be described later.

When the line relay I35 of the repeater energizes a bridge circuit is closed across the trunk conductors 200 and 202, which may be traced as follows: conductor 200, normally closed contacts controlled by armature I12, armature I90 and back contact, normally closed contacts controlled by armature -l 62, upper windings of relays I 33 and I28, front contact and armature I84, normally closed contacts controlled by armature I64, normally closed contacts controlled by armature I13, upper winding of relay I32, to conductor 202. Upon closure of this circuit, the line relay of the selector diagrammatically shown in Fig. 3 is energized. Upon energizing that line relay completes the circuit of a slow-acting release relay which operates to prepare the operating circuit of the selector in the usual manner and to place ground on the release trunk conductor 20I. The direct ground connected to conductor 2Ill will short circuit relay I4I of the repeater, which relay will thereupon deenergize, and at its armature I96 and back contact close the shunt circuit around the impulsing armature I84 of line relay I35 of the repeater. It can now be seen that with the shunt circuit completed upon the impulsing armature I84, further operation of the line relay I35 will have no effect upon the selector and the call can be extended no further. In order that this shunt circuit may not be completed around the impulsing armature I84, it is necessary that the calling party deposit a coin in the coin collect mechanism at the paystation A.

The person at the substation A now deposits a coin of suitable denomination in the coin collect mechanism provided for that purpose. This mechanism is well understood and the operation need not be explained in detail. When the coin is deposited it descends past the trigger mechanism which is released by the coin with the result that the polarized magnet of the coin collecting mechanism is connected to line conductor I2. The coin is held in suspense by a trap door where change.

it is adapted to be eithercollected or refunded under control of the polarized magnet. The coin may be deposited either before or 'after ,the receiver is removed. In either case the latter. op.- eration brings about" the operation of the rotary line switch 0, whereupon, the line is extendedto an idle selector, as has been described. 7

Assuming that the selector in Fig. v3 is the switch to which connection is extended, the operation is the same as has already been described and will not be repeated, with one exception, however: when the line conductors II and I2 are connected by the operation of the lineswitch C to the windings of the" line relay I35 and the impedance coil I39 the ground on line conductor I2 through the polarized magnet of the coin collect mechanism unbalances the differential relay I30 which is included in the line circuit and causes this relay to energize. It will be stated at this point that the polarized magnet at the substation is of high resistance and does not materially interfere with the transmission of operating impulses or with the talking circuit, but it is nevertheless suiiicient to cause relay I30 to operate as described.

Upon attracting itsarmature I10 relay I30 closes a circuit for relay tact and armature l9l and armature I86 to ground. Relay I34, upon energizing, establishes a locking circuit for itself at armature I18, thereby locking itself to release trunk conductor 20I, Relay I 34 at armature l8l prepares a circuit which will be described subsequently,'and at its armature I80 opens the shunt circuit around the impulsing armature I84, thereby obviously permitting extension of a call regardless of the operated or non-operated condition of relay I.

The party at paystation A may now operate his calling device in accordance with the digits necessary to operate theselector to seize one of the trunk circuits connected with the distant ex- In this case, assuming that the digit 0 is dialled by the party at substation A, the line relay I35 will be deenergized ten times and at armature I84 interrupts the circuit to the line relay of the selector ten times to cause the selector to step its wipers opposite the tenth level after which the selector is automatically rotated in the well knownv manner to select an idle one ofthe trunk circuits. When line relay I35 of the repeater deenergizes in response to the first impulse, slcw-to-release relay I31 is energized over the following circuit: ground by way of armature I62 and back contact, armature I83 and back contact, armature I81, and through the winding of relay I31 to battery. This relay thereupon energizes and in operating, at its armature l9| and front contact, completes the drcult of relay I29 from ground by way of armature I86, and the normally closed contacts 'controlled by armature I61 of the relay. Another result of the energizationof relay I31 is that at armature I90 and its front contact a direct bridge is placed across the trunk conductors 200 and 202 which does not include the upper windings of relays I33 and I 28. These circuit changes are made in order to reduce the resistance and impedance of the switch control circuit to a minimum during the transmission of impulses. Relay I29, upon operating at its armature I61, locks itself to the release trunk conductor 50, while at its armatures I65 and I 68 it short circuits the upper and lower windings of differential relay I30 included in the impulsing circuit of line relay I35.

I34 by way of bank con- 

